Microsoft's new Bing search engine now allows people to search and filter Twitter's massive stream of real-time data, an attention grabber for Bing and a potential new source of revenue for Twitter, the mushrooming social media site.

Bing's coup, announced Wednesday morning at the Web 2.0 Summit in San Francisco along with a second deal to search Facebook updates, was short-lived, however. Less than three hours later, Google said on its company blog that it, too, had reached a deal with Twitter that would allow Google "in the coming months" to follow the social site's up-to-the-minute updates.

The dueling announcements underlined the intensifying competition between Google and Microsoft over Internet search, even though 4-month-old Bing has only a tiny fraction of the search audience commanded by Google.

Still, some observers say "real-time search" may have only limited application for people other than news junkies, sports fanatics and others with a need to follow the minute-by-minute flow of information on the Web.

"There was a feeling that real-time search had gotten bigger and bigger, and (the large general search engines) could no longer ignore it," said analyst Greg Sterling, co-founder of Sterling Market Intelligence, adding, however, "Your mother-in-law and my mother-in-law are not necessarily going to use it, or care."

Recently valued at $1 billion, Twitter has experienced a burst of popularity this year, with almost one in five U.S. Internet users now tweeting, according to a report from the Pew Internet & American Life Project released Wednesday. The social-networking Web site has yet to show how it will make money, but payments from big search engines for real-time data could be one source of revenue.

In a statement, Google said access to Twitter would "make it easier for users to discover the most recent and relevant content on the web in Google search results. We have other ideas for how we can use this information to provide especially relevant information for our users, but we're not announcing any of those details today."

Microsoft also announced it has reached an agreement with Facebook that in the coming months will allow Bing users to search status updates posted by many of the Palo Alto-based social network's 300 million users. Facebook's chief operating officer, Sheryl Sandberg, said Wednesday that Microsoft was not paying for access to Facebook's data.

"We feel that today's announcement is a benefit to Facebook and Bing users alike and will increase their engagement and use of both services," Facebook said in a statement. "If they so choose, Facebook users get the opportunity to distribute information beyond Facebook and Bing search becomes more relevant and social than ever."

Facebook said it would put limits on the status updates that Bing will be able to search, blocking updates from minors ages 13 to 18 and allowing only Facebook status updates set to include "everyone" to be available to the search engine.

Bing's new Twitter service, which launched Wednesday afternoon at www.bing.com/twitter, allows people to pare down and evaluate the firehose-like stream of posts that pour out of the social media site, particularly on subjects that strike a social nerve at a particular time. Bing will elevate tweets it judges to be of greater relevance — including from people whose posts are frequently picked up and retweeted by others, or whose tweets include links to other news content.

"You're able to really improve the ability to search the Twitter stream," said Yusuf Mehdi, senior vice president of Microsoft's online audience business, who demonstrated the new Bing features to an audience of several hundred tech leaders and journalists in San Francisco.

For example, Mehdi demonstrated how a sports fan could use Bing to search Twitter for the latest news and opinion posts on the New York Yankees, showing how the search engine would tend to favor posts that include links to other news content for fans who want up-to-the-minute updates as the team plays in the American League Championship Series, or tweets from sources being followed by many people on Twitter.

Stefan Weitz, director of Bing Search, said virtually all of the development work for Bing's Twitter search was done at Microsoft's Silicon Valley campus in Mountain View. At least for the short run, until Google's real-time Twitter search is up, Bing will have an exclusive. "We were first," a clearly pleased Weitz said in an interview Wednesday.

Weitz and other Microsoft executives said the Twitter and Facebook deals were part of a "wave" of improvements Bing will continue to roll out. Microsoft launched the new search engine in early June.

"In 100 days, we've created some momentum," Weitz said of Bing. "We've got a lot more to come."